build libobjc via gnumake on windows

Modify the following line in makefile.dos in order to include gcc-4.0.1\libobjc\objc in header search path list
SUBDIR_INCLUDES = -I. -I.. -I../config -I./objc

I got the following error:
C:\>C:\Temp\make-3.80\WinRel\gnumake.exe -f makefile.dos
gcc -O2 -c -I. -I.. -I../config -I./objc hash.c
gcc -O2 -c -I. -I.. -I../config -I./objc sarray.c
gcc -O2 -c -I. -I.. -I../config -I./objc class.c
gcc -O2 -c -I. -I.. -I../config -I./objc sendmsg.c
sendmsg.c:32:21: tconfig.h: No such file or directory
sendmsg.c:33:23: coretypes.h: No such file or directory
sendmsg.c:34:16: tm.h: No such file or directory
sendmsg.c:38:26: runtime-info.h: No such file or directory
C:\Temp\make-3.80\WinRel\gnumake.exe: *** [sendmsg.o] Error 1

C:\>C:\Temp\make-3.80\WinRel\gnumake.exe -f makefile.in
process_begin: CreateProcess((null), LIBTOOL@ --mode=compile @CC@ -c -I. -I@glib
cpp_srcdir@ @CFLAGS@ -W -Wall -Wwrite-strings -Wstrict-prototypes @GTHREAD_FLAGS
@ -DIN_GCC -DIN_TARGET_LIBS -fno-strict-aliasing -I@glibcpp_srcdir@/objc -I@glib
cpp_srcdir@/../gcc -I@glibcpp_srcdir@/../gcc/config -I../../gcc -I@glibcpp_srcdi
r@/../include archive.c, ...) failed.
make (e=2): The system cannot find the file specified.
C:\Temp\make-3.80\WinRel\gnumake.exe: *** [archive.lo] Error 2